1. Field of the Invention
This invention is directed toward a work holder for holding a stack of disks to be worked on. The invention is more particularly directed toward a work holder for holding a stack of circular disks with a central mounting opening, such as CD disks and the like, the disks in the held stack to be worked in one operation to have a shape other than circular.
2. Description of the Related Art Including Information Disclosed Under CFR xc2xa71.97-1.99
It is known to provide CD disks in various shapes instead of the normal circular shape. A circular disk, with a central mounting opening and an annular section of recorded material on one side of the disk, concentric about the opening, is shaped by cutting or abrading to a new shape, other than circular, with the annular section of recorded material within the new shape. Usually, a plurality of circular disks are arranged in a stack and shaped in one operation to provide the disks in the stack with the new shape. The disks are usually stacked on a central pin via the central mounting opening and a nut is threaded onto the pin at the top to hold the stack in place. Alternatively, a collar may be mounted on the pin, pressed against the top of the stack, and locked to the pin with a set screw. However, it is a problem to hold the stack tight enough, without damaging the disks, so that the disks do not move during the shaping operation. Often one or more disks in the stack move during the shaping operation resulting in rejects and thus increasing production costs. It also takes time to mount the stacks.
It is the purpose of the present invention to provide a holder for a stack of disks which securely hold the disks during a shaping operation without damage to the disks. It is another purpose of the present invention to provide a holder for a stack of disks which can be quickly and easily loaded and unloaded with the stack of disks; and which holds each stack of disks, to be shaped, consistently with the same preselected force. It is another purpose of the present invention to provide a holder for a stack of disks which is compact and easily movable; and also which is quickly and easily located in the proper position at a work station so the stack of disks can be shaped.
In accordance with the present invention there is provided a disk stack holder having a support with a raised base on the support. A disk mounting pin slides through a hole in the base and support. One end of the pin, in the support, has connection means for use in connecting the pin to a pulling means. The other end of the pin, above the base, has a presser plate. A stack of disks are concentrically mounted about the pin between the top of the base and the presser plate. The pulling means are then actuated to draw the presser plate toward the base, and to lock it in position, to hold the stack tight between the presser plate and the base.
Preferably the other end of the pin has a stop. The presser plate has an opening shaped to allow it to be mounted on the pin over the stop and then moved laterally to have the stop prevent its withdrawal back off the pin. This construction allows the disks to be easily and quickly loaded onto, and removed from, the pin. Preferably the stop is adjustable toward or away from the other end of the pin. This allows the force, with which the holder clamps the stack of disks, to be adjusted.
The pulling means preferably has a cam member connected to the pin adjacent the one end of the pin. Movement of the cam member, in one direction transverse to the pin, will cam the pin downwardly to compress the stack between the presser plate and the base to securely hold the stack so that the disks in the stack can be shaped in one operation. Movement of the cam member in the opposite direction to the one direction will allow the pin to move upwardly to unlock the stack allowing it to be removed. The cam member is preferably moved by a lever mechanism located primarily outside the support.
The bottom of the support is preferably recessed with a seal around the recess. The recess is used to mount the holder on a pad on a table at a work station, the pad locating the holder in the correction position relative to the shaping tool, with the seal contacting the table. The recess is shaped and sized relative to the pad to provide a thin chamber between the pad and the bottom of the recess. Air can be withdrawn from this chamber, through the pad, to hold the holder in the correct position on the pad by suction.
The invention is particularly directed toward a disk stack holder having a support with a base thereon. A disk mounting pin slides through a hole in the base and the support with one end of the pin within the support. The other end of the pin is above the base. Connecting means are provided at the one end of the pin for use in connecting the pin to a pulling means. A presser plate is provided at the other end of the pin. The pulling means can pull the pin down pulling the presser plate toward the base to tightly clamp, and lock, a stack of disks on the pin between the presser plate and the base.